Electron tube for producing ultra short waves



Sept. 14, 1937. w. E. KUHLE El AL ELECTRON TUBE FOR PRODUCING ULTRASHORT WAVES Filed July 22, 1935 Z mm, "0,. mm. in

INVENTOR WILHELM EBEHHARD KUHL E FELI E PslGEP. BY

ATfoR'N'EY Patented Sept. 14, 1937 PATENT OFFICE ELECTRON TUBE FORPRODUCNG ULTRA SHORT WAVES Wilhelm Eberhard Kiihle and Felix Herriger,

Berlin, Germany, assignors to Telefunlren Gesellschaft fiir DrahtloseTelegraphie m. b. H.,

rlin, Germany, a corporation of Germany Application July 22, 1933,Serial No. 681,704

In Germany July 22, 1932 1 Claim. (01. 250-215) The invention isconcerned with electron or thermionic tubes adapted to the generation ofultra short waves of less than 1 meter (so-called decimeter waves). Itis known from the prior art that in tubes of the said sort which areoperated in what is known as a Barkhausen- Kurz circuit schemepredicated upon a positive grid and a negative anode, the grid and theanode, upon two opposite ends or sides of the tube, may

be provided with leads so that, at one end the direct current supplylead may be connected, and at the opposite end the antenna. by the aidof parallel wires (Lecher wires).

The present invention is particularly concerned with the constructionand mounting of such a tube, more especially with the mode of holding orsupporting both grid and anode. In tubes of the kind here mentioned andknown in the prior art, the supply leads of grid and anode consist 0 ofslender flexible wires so that for the supporting and anchoring of theseelectrodes, special means such as glass rods, metallic supporter wiresand equivalents, for instance, were required. Allof this, however, tendsto complicate the construction and mounting and renders diflicult moreparticularly the exact centering of the electrode system or assembly,while at the same time the losses occasioned within the tube are raised.

According to this invention, the lead-ins are in the form of rigidrodlets, for instance, made of tungsten or molybdenum, while grid andanode are directly secured thereto with the re-' sult that they aresupported by the supply leads at two ends.

One embodiment of the said idea is illustrated in Figure 1. Figure'zshows a cross-section of the electrode assembly of Figure 1.

Referring to the same, I denotes the glass vessel or bulb having at twoopposite ends the re- 40 entrant portions and presses 2 and 3 inwhichlatter are sealed by fusion the anode supporter wires 4, 5, and the gridsupporter wires 6, I. The cylindrical anode 8 by the aid of a slendermetal tubelet 9 which itself may constitute part 'of the anode sheet, isshifted upon the leads 4 and 5. The grid III in a similar manner issecured by the aid of two tubelets or sleeve members II and I2 upon itssupply leads 6 and I.

Another reentrant portion and press l3 contains the leads l4, l5 for thefilament IS. The cathode wire or filament is directly welded onto one ofthe supply leads ll, whereas it is united with the other wire l5 by wayof a leaf spring l1 5 rather than immediately. The leaf spring I1 isconductively bridged by means of 'a flexible litzen-wire (stranded wire)l8, otherwise it would be unduly heated by the heating (filament)current.

Figure 2 shows a cross-section of the electrode assembly fromgyvhich themounting of the tube can be clearly understood. The anode and the grid,at the side facing towards the cathode press, have each a slot I 9 and20, respectively. These 15 slots which are radially arranged withrespect to the grid and anode axes make it possible to slip the cathodethrough said slots and into the grid-anode'system after the latterelectrodes have been mounted upon their supporter wires.

The sleeves marked II and I 2 are rigidly connected with the grid bywelding. Sleeve I2 is also rigidly connected with the grid supportingwire], while sleeve I I is arranged so as to slide on wire 6 for reasonspertaining to assembling and the 25 thermal expansion of the grid. Thesame holds true for sleeve 9 and wire 4. Leaf spring I? serves fortensioning the.cathode which expands when heated.

We claim: 30

An electron discharge'tube comprising a cathode, grid and anodeelectrodes substantially surrounding the cathode, each of said grid andanode electrodes being provided at opposite ends with sleeve membersupport rods extending in a direction parallel to the cathode connectedto said sleeve members at corresponding ends of said electrodes andrigidly mounting said electrodes, and additional support rods alsoextending in a direction parallel to the cathode connected to the 40sleeve members at the opposite and corresponding ends of said electrodesand forming therewith a 'slidable connection for permitting expansion ofsaid electrodes in a longitudinal directionbut not in a transversedirection. 45.

WILHELM EBERHARD 'KfiHLE. FELIX HERRIGER.

